John IV, Duke of Oświęcim

Jan (or Janusz) IV Oświęcimski (of Oświęcim, or Gliwicki - of Gliwice) (between 1426 and 1430 – around 1496) was the duke of Oświęcim from 1445 to 1456 and duke of Gliwice from 1465 to 1482.

He was the son of Kazimierz I Oświęcimski and Anna Żagańska. When his father died around 1433/1434 he was underage and his lands were governed by his brother, Wacław I Zatorski. In 1438, Jan, Wacław, and their brother Przemysł agreed to became vassals of the King of Poland in exchange for the rights to govern the Duchy of Zator (it would be given to them in 1440 and in 1441 Wacław would officially become a vassal).

On January 19, 1445, the territories governed by Wacław were partitioned between the brothers. Jan became the duke of Oświęcim, ruling the duchy of Oświęcim, which included the towns of Oświęcim, Kęty, Żywiec and half of Gliwice. Although in 1447 he signed a border agreement with Kingdom of Poland, soon their relations worsened, as together with his brothers he opposed the Polish bishop and cardinal Zbigniew Cardinal Oleśnicki who took control of Duchy of Siewierz. This has led to increased tensions between him and the Polish nobles, even resulting in some border wars (common for that period in medieval Europe). In 1452, Jan looted Polish borderlands and even approached Kraków, the Polish capital itself, on a daring raid. In 1453, a large Polish army invaded his Duchy in retribution, and Jan was given a choice—vassalization or selling of the Duchy. Defeated, in 1454 he agreed to sell the Duchy to Kingdom of Poland for 20,000 groszes.

Jan briefly joined the Prussian Confederation army as a mercenary during the Thirteen Years' War (one of the Polish-Teutonic Wars). However, the Polish king, Casimir IV Jagiellon, delayed full payment of promised amount for the Duchy and he returned to his homeland with mercenaries and allies from Prussia; stirring up resentment. Eventually, in 1458, the Polish king decided to pay him fully to stop the troubles (he would finish the payment in 1462). In 1460, after the death of Bolko V Husyta, Duke of Opole, Jan tried to claim his domain, but was defeated by brother of Bolko, Mikołaj I Opolski. In 1462, with money from the Polish king, he bought Gliwice with its castle from his brother, Przemysław Toszecki, as well as nearby Ujazd from the bishops of Wrocław and he became the duke of Gliwice in 1465.

In 1471, he supported the election of Vladislaus II of Bohemia and Hungary to the throne of Bohemia, incurring the wrath and raiding from his contender, Matthias Corvinus of Hungary. In 1475 Matthias captured Jan, forcing him to give up half of his lands and later, vassalizing him. In 1482, Jan sold the rest of his lands in Gliwice; in 1484 he inherited lands after his brother Przemysław—but almost immediately they were confiscated by Matthias, who claimed more dubious rights to them—but backed them with a much larger army.

Married twice, in his last years he retired to his wife's estate in Karniów, Jan is best remembered as the last Duke of Oświęcim and the male representative of his of his line of Silesian Piasts.

References

*pl icon [http://www.poczet.com/janiv.htm Jan (Janusz) IV Oświęcimski (Gliwicki)] (genealogy, heraldics, timeline)

Further reading

* Krzysztof Rafał Prokop, "Księstwa oświęcimskie i zatorskie wobec Korony Polskiej w latach 1438-1513. Dzieje polityczne", Polska Akademia Umiejętności, Kraków 2002
* Marcin Spórna, Piotr Wierzbicki, "Słownik władców Polski i pretendentów do tronu polskiego", Wydawnictwo Zielona Sowa, Kraków 2003
* Stanisław Szczur, Krzysztof Ożóg, "Piastowie", Wydawnictwo Literackie, Kraków 1999